Then just get rid of tips, add 20% to your prices, pay your staff properly and manage them. If they perform badly train them better, promote and give pay rises

Then just get rid of tips, add 20% to your prices, pay your staff properly and manage them. If they perform badly train them better, promote and give pay rises to the best staff. If you really wanted to have a bonus system based on customer feedback. You know, the way normal business work.